31,777 research outputs found

    Non-self-adjoint resolutions of the identity and associated operators

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    Closed operators in Hilbert space defined by a non-self-adjoint resolution of the identity \{X(\lambda)\}_{\lambda\in {\mb R}}, whose adjoints constitute also a resolution of the identity, are studied . In particular, it is shown that a closed operator BB has a spectral representation analogous to the familiar one for self-adjoint operators if and only if B=TAT−1B=TAT^{-1} where AA is self-adjoint and TT is a bounded operator with bounded inverse

    Preparations of methoxynitrophenazines and their photoconductivities

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    Eight methoxynitrophenazines with a methoxy group at the 1 or 2 position and a nitro group at the 6-, 7-, 8- or 9-position of the phenazine ring 1,6, 1,7. 1,8, 1,9, 2,6, 2,7, 2,8 and 2,9 were prepared and their photocurrents were measured by illuminating the surface-type cell with white light from a W lamp under a N atmosphere at room temp. The photocurrents of 1-nitrophenazine 6 and 2-nitrophenazine 7 are compared with those of the methoxynitrophenazines. The photocurrent (i sub p) increases with increasing light intensity (I), thus satisfying log i varies as n log I. The n values are 0.5-1.0. When the nitro group is located at the beta-position of the phenazine ring, the photocurrent becomes larger owing to the electron withdrawing property of the nitro group. On the other hand, the photocurrents of phenazines with the nitro group at the Alpha-position are extremely small. The photoconductivities of methoxynitrophenazines are lower in air

    Vortex simulation of forced mixing layers

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    Two-dimensional, spatially growing, turbulent mixing layers are simulated numerically by a vortex method and the results are compared with those determined experimentally. The effects of artificial forcing on flow development are also studied. Many of the flow features which have been observed experimentally are reproduced, and good quantitative agreements between experiments and computations are obtained

    Biospheric context of Siberian development

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    Recent publications on human appropriation of Net Primary Production (NPP) raise the question of how much of the biosphere’s productivity we can appropriate in a sustainable way. This article brings the issue into the context of Siberian development. In contrast to many other regions of the world, the population density in Siberia is still very low as compared to the NPP supplied by regional ecosystems. Hence, it is not too late to raise the question on how much of the NPP supplied by Siberian ecosystems we can appropriate in a sustainable way
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